The recommendation for war is imminent.
Carlos Alcaraz highlighted this by using two emojis – a number one and a post on Estagram accompanying his pre-ATP finals on Friday.
Whether Alcaraz or sinner ends the year number in the world is a key point of interest in the final event of the season in Turin.
Ending a long and frustrating season as the best player on tour is a prestigious accolade, rewarding their beauty and consistency over the last 12 months.
The 24-year-old Italian has been out of action for three months, having been banned for failing two doping tests.
In the end Alcaraz of Spain finally started his rival in the rankings in September, ending the 65-week week of the Sinner by winning the last grand slam of 2025 in New York.
Now the clear two-horse race goes to the final event of the season, with 22-year-old Alcaraz looking the favorite to win their duel.
“If Carlos plays well without a chance, it doesn’t matter what my result is,” said the sinner.
BBC Sport analyzes the permutations for each player and who might stop them. At the bottom of the page, you can vote for who you think will win in Turin.